Ghost blog uses cloudinary or s3 as storage.
Use Cloudinary image storage module for Ghost blog write by eexit. Use can build your own docker image with Dockerfile or use my pre-build docker image yunfandev/ghost:cloudinary.
Use AWS S3 storage module for Ghost blog write by colinmeinke. Use can build your own docker image with Dockerfile or use my pre-build docker image yunfandev/ghost:s3.